Microplastics are found in all parts of the environment and in food, but the scientific quality of the knowledge available is insufficient to conclude with certainty about consequences microplastics have on the environment and on health in Norway.
This is the key message of a risk assessment from the Norwegian Scientific Committee for Food and Environment (VKM).
The Scientific Committee itself initiated the work, recognizing a need for an overview of available knowledge and data on microplastics. Among other things, VKM wanted to examine the effects microplastics have on the Norwegian environment and health.
In recent years, a great deal of scientific literature on microplastics has been produced. VKM points out that the quality of the research is insufficient to assess whether microplastics pose a risk to the environment and to human health. All the methods used have variable quality, according to VKM. About half of the articles reviewed by VKM were excluded for their lack in quality.
“Researchers use many different approaches to study microplastics. That is to be expected in a field of research under development, but it is a challenge for risk assessment because it limits the possibilities for comparing data,” says Professor emeritus Janneche Utne Skåre, the academic leader of the project group.
“The research communities need to talk. We need collaboration, a holistic perspective and harmonization of methods to improve quality and to be able to compare studies,” continues Skåre.
VKM's literature search revealed shortcomings in the data on levels of microplastics found in the environment in Norway and in Nordic countries. Most of the data is from water columns and surface water, and from living organisms in the ocean. Data from fresh water and soil is limited, as compared to data from the sea.
VKM concludes that there is very limited good quality data about levels of microplastics in the Norwegian environment.
“When it comes to levels of microplastics found in food products in Norway, the scope of data having an acceptable quality is very limited. Many food groups, such as meat, vegetables and dairy products, have not been studied at all,” says Skåre.
According to VKM, we need more knowledge about the sources of microplastics, and need to understand how microplastics are spread in the Norwegian and Nordic environment.
“Efforts should be directed towards land and freshwater systems,” Skåre points out.
VKM concludes that available research is insufficient for VKM to be able to assess the risk that microplastics pose to people's health. VKM has studied the oral ingestion of microplastics, and absorption through the gastrointestinal tract.
There is more research available on microplastics and environmental hazards, but this also has limitations.
“Globally, the risk to the environment is low. For marine ecosystems relevant to Norway, the overall risk is low. For the most polluted sites in the North Sea and Sweden, there is a potential risk. The knowledge gaps are so large that these conclusions must be regarded as temporary,” says Skåre.
VKM's risk assessment is based on assessments from the European Food Safety Authority (EFSA), the United Nations Food and Agriculture Organization (FAO) and the European Commission's Science Advice for Policy, SAPEA, from 2016, 2017 and 2019 respectively.
In addition, VKM made its own systematic literature search, with almost 2000 results. A large majority of the findings were of insufficient quality, and a total of 274 scientific publications from the search were included.
VKM's steering group is responsible for the assessment.